package com.imooc.netty;

import com.imooc.SpringUtil;
import com.imooc.enums.MsgActionEnum;
import com.imooc.service.UserService;
import com.imooc.service.impl.UserServiceImpl;
import com.imooc.utils.JsonUtils;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.channel.group.ChannelGroup;
import io.netty.channel.group.DefaultChannelGroup;
import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
import io.netty.util.concurrent.GlobalEventExecutor;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.DependsOn;

import java.util.ArrayList;
import java.util.List;

/**
 * @author 朝花不迟暮
 * @version 1.0
 * @date 2020/12/28 22:52
 */
//@DependsOn("springUtil")
public class ChatHandler extends SimpleChannelInboundHandler<TextWebSocketFrame>
{
    //用户记录和管理所有客户端的channel
    public static ChannelGroup clients = new DefaultChannelGroup(GlobalEventExecutor.INSTANCE);

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, TextWebSocketFrame msg) throws Exception
    {
        //获取客户端传输的消息
        String content = msg.text();
        Channel currentChannel = ctx.channel();

        // 1. 获取客户端发来的消息
        DataContent dataContent = JsonUtils.jsonToPojo(content, DataContent.class);
        Integer action = dataContent.getAction();
        // 2. 判断消息类型，根据不同的类型来处理不同的业务
        if (action.equals(MsgActionEnum.CONNECT.type))
        {
            // 	2.1  当websocket 第一次open的时候，初始化channel，把用的channel和userid关联起来
            String senderId = dataContent.getChatMsg().getSenderId();
            UserChannelRel.put(senderId, currentChannel);

            // 测试
            for (Channel c : clients)
            {
                System.out.println(c.id().asLongText());
            }
            UserChannelRel.output();
        } else if (action.equals(MsgActionEnum.CHAT.type))
        {
            //  2.2  聊天类型的消息，把聊天记录保存到数据库，同时标记消息的签收状态[未签收]
            ChatMsg chatMsg = dataContent.getChatMsg();
            String msgText = chatMsg.getMsg();
            String receiverId = chatMsg.getReceiverId();
            String senderId = chatMsg.getSenderId();

            // 保存消息到数据库，并且标记为 未签收
            UserService userService = SpringUtil.getBean(UserServiceImpl.class);
            String msgId = userService.saveMsg(chatMsg);
            chatMsg.setMsgId(msgId);

            DataContent dataContentMsg = new DataContent();
            dataContentMsg.setChatMsg(chatMsg);

            // 发送消息
            // 从全局用户Channel关系中获取接受方的channel
            Channel receiverChannel = UserChannelRel.get(receiverId);
            if (receiverChannel == null)
            {
                // TODO channel为空代表用户离线，推送消息（JPush，个推，小米推送）
            } else
            {
                // 当receiverChannel不为空的时候，从ChannelGroup去查找对应的channel是否存在
                Channel findChannel = clients.find(receiverChannel.id());
                if (findChannel != null)
                {
                    // 用户在线
                    receiverChannel.writeAndFlush(
                            new TextWebSocketFrame(
                                    JsonUtils.objectToJson(dataContentMsg)));
                } else
                {
                    // 用户离线 TODO 推送消息
                }
            }
        } else if (action.equals(MsgActionEnum.SIGNED.type))
        {
            //  2.3  签收消息类型，针对具体的消息进行签收，修改数据库中对应消息的签收状态[已签收]
            UserService userService = (UserService) SpringUtil.getBean("userServiceImpl");
            // 扩展字段在signed类型的消息中，代表需要去签收的消息id，逗号间隔
            String msgIdsStr = dataContent.getExtand();
            String[] msgIds = msgIdsStr.split(",");

            List<String> msgIdList = new ArrayList<>();
            for (String mid : msgIds)
            {
                if (StringUtils.isNotBlank(mid))
                {
                    msgIdList.add(mid);
                }
            }

            System.out.println(msgIdList.toString());

            if (msgIdList != null && !msgIdList.isEmpty() && msgIdList.size() > 0)
            {
                // 批量签收
                userService.updateMsgSigned(msgIdList);
            }
        }
    }

    /**
     * @Description: 当客户端连接服务端之后, 获取到客户端的channel, 并且放到channelGroup中
     * @Param: ctx
     * @return:
     * @Author: 朝花不迟暮
     * @Date: 2020/12/28
     */
    @Override
    public void handlerAdded(ChannelHandlerContext ctx) throws Exception
    {
        Channel channel = ctx.channel();
        clients.add(channel);
    }

    @Override
    public void handlerRemoved(ChannelHandlerContext ctx) throws Exception
    {
        clients.remove(ctx.channel());
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception
    {
        cause.printStackTrace();
        // 发生异常之后关闭连接（关闭channel），随后从ChannelGroup中移除
        ctx.channel().close();
        clients.remove(ctx.channel());
    }
}
